Thread: 'Need some advice',,

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just picked up my '32 coupe today,,parked it in the garage{which has a door that leads into the house}and I guess it's been a while since I had a "carburetor"car because the gas fumes are making their way into the house!!
Any advice other than park it outside???
Thanks,George

What type of fuel lines did the builder use from the tank to the engine? If it's a stainlees steel braided type of fuel line, some are known to allow gas odors. You're going to have to investigate the source yourself, remember with gas, it's the vapors that ignites not the liquid.

Mike

Mike,,I'll check on the lines,but won't all "carburetor" cars have a gas smell since there is always some fuel in the bowl?

I've never smelled raw fuel from a carb without there being a leak somewhere, or if it was flooded.

George,
The carbs indeed have raw fuel in the bowls, but they should not be giving you strong fumes. You're going to need to crawl over, under & around sniffing for the fume source like Mike says. Sniff around your engine/carbs, fuel tank vent hose, supply line fittings, pump fittings, etc. You don't have float levels set too high, dripping raw fuel into the blower, do you? You should not have fuel fumes that strong, IMO, and I chased them for weeks, too. Mine ended up being more tied to my running mixture, leaving excess raw fuel in the intake. Have your carbs been tuned specific to your engine?

I'll give all the lines a "good look over"!!!!
Thanks Rodger and everyone else!!!

ps,,,,,,I LOVE this rod,,I'll post some nice pics in a few days

Other then an obvious leak, which any one off, hand built car is susceptible to, the most suspect place is the gas tank vent. Somewhere here I have a fairly long thread from a couple years ago that I went through several tank vent "designs" to eliminate those fumes. I tried to find the thread, but it's too early After spending hours working on the problem, I still have a little gas smell if the car is brought in after a run, but it does go away over night. The car is in my basement shop this winter and with an almost full gas tank - not a sniff of gas (and guys, no preaching on those dangers, it was supposed to have been drained, but CRS set in and I put the winter "door" in place before it happened)

do the fumes remain after the car has cooled down ? the heat may be peculating the fuel in the bowl . which will dribble in to the intake. a phenolic spacer helps this. another way is to have a kill switch for the fuel pump. shut it down before killing the engine to lower the bowl level.

I have 2 stored that have carb- plus the fuel tank topped off- not a hint of fumes- sounds like you have a leak somewhere-

On a supercharged engine, the blower WILL DRAW and PUSH fuel/air mixture thru the cylinders on cam valve overlap and pump raw unburnt mixture into the exhaust system which will exit UNBURNT and stinkie------

If your selling that much gas the odds are that your carb is leaking down and putting gas into the intake. Is it hard to start after sitting for a while?

Originally Posted by jerry clayton

On a supercharged engine, the blower WILL DRAW and PUSH fuel/air mixture thru the cylinders on cam valve overlap and pump raw unburnt mixture into the exhaust system which will exit UNBURNT and stinkie------

So true of a blower motor.

Originally Posted by jerry clayton

On a supercharged engine, the blower WILL DRAW and PUSH fuel/air mixture thru the cylinders on cam valve overlap and pump raw unburnt mixture into the exhaust system which will exit UNBURNT and stinkie------

Originally Posted by DA34GUY

So true of a blower motor.

So Jerry & Don,
Having never owned a blower motor, what can be done to alleviate this? Switch off the fuel and starve the engine on shutdown before turning off the spark?

various things--carb wok helps some things as its probably over rich


widening the cam lobes lets the exhaust close more before the intake opens and cuts down on the time for the blow thru

remember that I got in trouble talking about his starter mount!!!

Since you garage your rod, I would recommend keeping a window, or side door cracked open. Regardless, if your still smelling fumes, the extra air/oxygen will
help keep your water heater, or gas dryer from igniting those fumes ....make sure your tank is vented correctly.